Every designer eventually hits a task specific enough that no existing script covers it — and hiring a developer for a five-minute automation isn't practical. This video walks through using Google Antigravity as an AI coding assistant to generate custom Illustrator ExtendScript from a plain-language description, cutting a normally multi-hour build down to minutes.
Key Features & Specifications
- No prior JavaScript or ExtendScript experience required
- Works for one-off custom tasks as well as reusable tools
- Output is standard .jsx, compatible with Illustrator 2021–2026 (CC)
- Iterative workflow — refine the script by describing bugs in plain language rather than debugging code directly
Writing Prompts That Produce Working Scripts
An AI coding assistant cannot see your screen, your layers panel, or the document you have open. Everything it knows about your task comes from the words you type, which is why the prompt is the entire job. A vague prompt like "make my logos smaller" can mean a dozen different things: scale the artwork, shrink the artboard, resize the document, or change the export dimensions. The AI has to guess, and guesses produce broken scripts.
A working prompt describes three things explicitly: the starting state (what is selected and how the document is set up), the transformation (the action to perform), and the end state (what the document should look like when finished). Write those three sentences before you ask for anything, and the first draft will be dramatically closer to correct.
It also helps to state your constraints up front. Mention your Illustrator version, whether the script should work on the active document or a whole folder of files, and whether you want a settings dialog or a silent one-click run. Each constraint you name is one fewer assumption the AI has to make. The checklist linked at the bottom of this post is the exact set of details worth nailing down before you generate.
A Little ExtendScript Knowledge Goes a Long Way
You do not need to write code for this workflow, but knowing a handful of ExtendScript concepts makes steering the AI much faster. Illustrator scripts think in a hierarchy: the application contains documents, documents contain layers, layers contain page items, and your selection is a subset of those items. Most generated-script failures stem from a wrong assumption somewhere in that chain.
Two more facts are worth knowing. First, Illustrator's ExtendScript engine
speaks an older JavaScript dialect (ES3), so modern syntax the AI might reach
for — arrow functions, let and const, template
literals — will throw errors. If you see a syntax error on otherwise
sensible-looking code, telling the AI "use ES3-compatible syntax" usually
fixes it in one round. Second, scripts run with full access to the
application, which is exactly why you test on copies: a script can delete,
move, or rename anything in the open document, and there is no recycle bin for
a bad loop.
Step-by-Step: Build Process
- Write a precise, plain-language description of the task: what gets selected, what changes, and what the end result should look like.
- Generate an initial script draft and test it immediately on a sample file — never a production file on the first run.
- If the output isn't right, describe exactly what happened versus what you expected, rather than just saying "it didn't work."
- Repeat until the script behaves consistently across a few different test files.
- Save the final version with a clear filename and a short comment block describing what it does.
Testing Safely: The Scratch-File Habit
Professional developers never test on live data, and the same discipline applies here. Keep a small folder of scratch files — duplicates of real work, plus a few deliberately awkward cases (empty layers, locked objects, grouped items, no selection at all). Run every new draft against the whole folder before it touches anything real. A script that works on one tidy file and explodes on the second is not done; it is a draft.
Version your drafts as you iterate (script_v1.jsx,
script_v2.jsx), so a regression in version four means falling
back to version three instead of debugging backwards. Keep the final version's
comment block honest about what the script expects and what it changes.
Common First-Draft Failures and What They Mean
| Symptom | Likely cause | What to tell the AI |
|---|---|---|
| Error: "Undefined is not an object" | The script assumed something exists — an open document, a selection, a named layer — that isn't there | "Check that a document is open and at least one item is selected before doing anything, and show an alert if not" |
| Script runs but nothing visibly changes | It operated on the wrong scope — the active layer instead of the selection, or vice versa | Describe exactly which objects should change: "only the selected items" versus "every item on layer X" |
| Wrong objects get modified | Selection scope too broad, or the script loops over the whole document | "Limit the operation to the current selection, and skip locked or hidden items" |
| Works on one file, fails on the next | Hardcoded names — a specific layer, swatch, or document name from your test file | "Don't assume any layer or document names; use the active document and active layer" |
Troubleshooting & Tips
The single biggest factor in getting a working script on the first or second try is specificity in your initial prompt — vague requests produce vague (and often broken) scripts. If you hit a wall on a specific Illustrator API method, paste the exact error text back in; error messages give the AI far more to work with than a general "it's not working."
One more tip: when several iterations still have not converged, split the task. Two small reliable scripts beat one clever, flaky script every time.
Conclusion
Google Antigravity turns plain-language descriptions into working Illustrator scripts in minutes, with no coding required. The entire skill comes down to prompt specificity: describe the starting state, the transformation, and the end state before you ask for anything. Always test generated scripts on scratch files first, and if iterations stall, split the task into smaller pieces. Write the prompt well, and the AI takes care of the code.
FAQ
Do I really need zero coding experience?
For the workflow itself, yes — describing the task precisely matters far more than syntax knowledge. The small amount of ExtendScript vocabulary covered above (documents, layers, selection, ES3) is helpful but optional; you can also just paste error messages back and let the AI do the translating.
Is AI-generated code safe to run?
Treat it like any code from the internet: test on copies first, and read through it at a high level before running. Scripts execute with full application access, so never run a generated script on a client file you cannot afford to rebuild until you have seen it behave on scratch files.
Does the generated .jsx work on both Mac and Windows?
Yes. ExtendScript is cross-platform; the only differences you will ever hit are file paths (which a well-prompted script asks you to choose via dialog rather than hardcoding).
Custom Script Prompt Checklist
The exact checklist used to describe Illustrator tasks precisely enough for reliable AI-generated scripts.